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    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <table border = "1" cellspacing = "0" width = "500" height = "300" cellpadding = "50" align = "center">
        <tr>
            <td>姓名</td> <td>性别</td> <td>年龄</td>
        </tr>
        <tr>
            <td>张三</td> <td>男</td> <td>18</td>
        </tr>
        <tr>
            <td>李四</td> <td>男</td> <td>19</td>
        </tr>
        <tr>
            <td>小美</td> <td>女</td> <td>16</td>
        </tr>
    </table>

    <br/>

    <table border = "1" cellspacing = "0" width = "500" height = "300"  align = "center">
        <thead>
            <th>姓名</th> <th>性别</th> <th>年龄</th>
        </thead>
        <tbody>
        <tr>
            <td>张三</td> <td>男</td> <td>18</td>
        </tr>
        <tr>
            <td>李四</td> <td>男</td> <td>19</td>
        </tr>
        <tr>
            <td>小美</td> <td>女</td> <td>16</td>
        </tr>
        </tbody>
    </table>
        
    <br/>

    <table border = "1" cellspacing = "0" width = "500" height = "300" cellpadding = "50" align = "center">
        <tbody>
        <tr>
            <td>姓名</td> <td>性别</td> <td>年龄</td>
        </tr>
        <tr>
            <td>张三</td> <td rowspan = "2">男</td> <td>18</td>
        </tr>
        <tr>
            <td>李四</td>  <td>19</td>
        </tr>
        <tr>
            <td colspan = "2">小美</td>  <td>16</td>
        </tr>
        </tbody>
    </table>

</body>
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